JP5061320B2 - Water treatment reactor, water treatment system, and water treatment method - Google Patents

Description

  The present invention relates to a water treatment reactor, a water treatment system, and a water treatment method. Specifically, the present invention relates to a water treatment reactor for combined use of ozone and hydrogen peroxide.

  Conventionally, ozone treatment is applied in a water treatment system, and it is used for various water treatments such as water and sewage and industrial wastewater from factories. In recent years, an accelerated oxidation treatment technique that further increases the treatment speed has been established.

  Ozone treatment is a water treatment technique that uses the oxidizing power of ozone to oxidize and decompose organic substances in water. In the ozone treatment, the target substance is oxidatively decomposed by two routes, namely, a reaction by ozone molecules and a reaction by hydroxyl radicals generated by decomposing ozone. Hydroxyl radical is a substance having high oxidizing power, and oxidative decomposition of a substance that cannot be decomposed by ozone is possible. For this reason, water treatment technology that promotes decomposition of a hardly ozone-decomposable substance by combining ozone with hydrogen peroxide, ultraviolet light, etc., and promoting the generation of hydroxyl radicals, that is, an accelerated oxidation treatment method is promising ( For example, see non-patent documents 1 and 2).

In the ozone / hydrogen peroxide treatment method, which is a kind of the accelerated oxidation treatment method, the injection amount of hydrogen peroxide affects the processing efficiency. From the viewpoint of the molar ratio (weight ratio) with ozone injected as a gas, a ratio at which good treatment efficiency is obtained is obtained, and injection control has been performed based on the ratio (for example, see Patent Documents 1 and 2).
Kenichi Hamada, “Research on development of wastewater treatment system by ozone / hydrogen peroxide treatment method”, Kyoto University Doctoral Dissertation (Doctor), p53-p85 (2002) Takuharu Iwamoto et al., “Basic Study of AOP Combined Ozone Contact Pond (II)”, 15th Annual Meeting of the Japan Ozone Society, p45-p48 (2005) JP-A-9-276882 JP-A-10-165971

  However, since the ratio at which the above-described good treatment efficiency is obtained varies depending on the quality of the water to be treated such as organic substance concentration, pH, water temperature, and the injection rate of ozone gas, it is necessary to experimentally examine it in advance. In addition, in the case of actual environmental water whose water quality varies, the ratio of hydrogen peroxide to ozone that can achieve good treatment efficiency is also considered to change due to the fluctuation of water quality. Is difficult. Furthermore, since the ratio between hydrogen peroxide and ozone differs depending on the apparatus, even if the ratio obtained on the laboratory scale is applied to an actual plant as it is, the processing efficiency similar to the experiment is not always obtained.

  In addition, the inventions disclosed in Patent Documents 1 and 2 increase the ozone absorption efficiency of the ozone contact tank to which the accelerated oxidation treatment is applied, prevent ozone and hydrogen peroxide from being excessively injected, The purpose of the present invention is to provide a control method. In any of the inventions, in the ozone contact tank, from the “preset hydrogen peroxide and ozone injection rate”, the driving of each ozone generator and the hydrogen peroxide injection rate. The main content is the method of controlling the. In addition, the valve opening target value of hydrogen peroxide is determined and adjusted so that the excess dissolved ozone concentration is constant, so the injection rate of hydrogen peroxide and ozone is not set. In addition, it is difficult to maximize the effect of accelerated oxidation.

  Therefore, the object of the present invention is to provide a water treatment reactor for obtaining good treatment efficiency regardless of external factors such as the quality of the water to be treated and its fluctuation, the injection rate of ozone gas, the shape of the reactor, and the like. A treatment system and a water treatment method are provided.

  The above object of the present invention is achieved by the following means.

(1) That is, the present invention relates to ozone gas injection means for injecting ozone gas into the water to be treated, hydrogen peroxide injection means for injecting hydrogen peroxide into the water to be treated, and the concentration of dissolved ozone in the water to be treated. A water treatment reactor having a dissolved ozone concentration measuring means for measuring, wherein the hydrogen peroxide injection means has a dissolved ozone concentration measured by the dissolved ozone concentration measuring means less than a lower limit value of a reliable measurement range. The water treatment reaction tank is characterized in that the injection amount of the hydrogen peroxide is controlled.

(2) In the water treatment reactor according to (1), the hydrogen peroxide injection unit may control the hydrogen peroxide injection amount to be a minimum. is there.

(3) The present invention also includes at least one water treatment reaction tank, wherein the water treatment reaction tank includes ozone gas injection means for injecting ozone gas into the water to be treated, and hydrogen peroxide as the water to be treated. A water treatment system having hydrogen peroxide injection means for injecting into the water and dissolved ozone concentration measurement means for measuring the concentration of dissolved ozone in the water to be treated, wherein the hydrogen peroxide injection means includes the dissolved ozone concentration In the water treatment system, the injection amount of the hydrogen peroxide is controlled so that the dissolved ozone concentration measured by the measuring unit is less than the lower limit value of the reliable measurement range.

(4) The water treatment system according to (3), wherein the hydrogen peroxide injection unit controls the injection amount of the hydrogen peroxide to be a minimum.

(5) The present invention also measures an ozone gas injection step of injecting ozone gas into the water to be treated, a hydrogen peroxide injection step of injecting hydrogen peroxide into the water to be treated, and a concentration of dissolved ozone in the water to be treated. A dissolved ozone concentration measuring step, wherein the hydrogen peroxide injection step is such that the concentration of the dissolved ozone measured by the dissolved ozone concentration measuring step is less than a lower limit value of a reliable measurement range. Thus, the water treatment method is characterized in that the injection amount of the hydrogen peroxide is controlled.

(6) The water treatment method according to (5), wherein the hydrogen peroxide injection step is controlled so that the injection amount of the hydrogen peroxide is minimized.

  According to the present invention, as a result of controlling the injection amount of hydrogen peroxide so as to minimize the dissolved ozone concentration, the amount of hydroxyl radicals generated increases, so water purification ability, that is, agricultural chemicals, household goods, pharmaceuticals, etc. The ability to oxidatively decompose various toxic chemicals and odorous substances can be maximized.

  In addition, according to the present invention, the injection amount of hydrogen peroxide is controlled by the dissolved ozone concentration that can be continuously monitored, so the quality of the water to be treated and its variation, the change in the injection rate of ozone gas, It is possible to respond quickly and similarly, without depending on the shape of the apparatus.

  Furthermore, according to the present invention, unlike the prior art, since it is not necessary to calculate the ratio of hydrogen peroxide and ozone in advance or during work, the work efficiency is improved and the economic burden on the work is further increased. Can be reduced.

  In addition, according to the present invention, since the minimum injection amount of hydrogen peroxide can be calculated, it is possible to reduce the economic burden due to the use of excess hydrogen peroxide while maintaining good processing efficiency. Can do.

  Furthermore, according to the present invention, since the dissolved ozone concentration calculated in the prior art is applied to control the injection amount of hydrogen peroxide, the existing apparatus can be used, and the economic burden on the apparatus is reduced. Similarly, the degree of freedom and versatility of device design can be increased.

  In addition, according to the present invention, by keeping the dissolved ozone concentration at the minimum concentration, it is possible to keep the production concentration of bromate ions, aldehydes, and the like of carcinogenic substances formed by the reaction of ozone and bromide ions in raw water. it can.

  Furthermore, according to the present invention, since the hydrogen peroxide and dissolved ozone concentrations are kept at the minimum concentration, the life of the activated carbon and the chlorine agent in the activated carbon treatment and chlorination after the ozone / hydrogen peroxide treatment step. Residues of hydrogen peroxide and dissolved ozone, which can adversely affect the consumption of water, can be minimized.

  Further, according to the present invention, since the control factor is only the injection amount of hydrogen peroxide, the structure of the instrumentation equipment can be simplified, the efficiency of the apparatus can be improved, and the failure can be reduced.

  Furthermore, according to the present invention, since hydroxyl radicals having extremely high reactivity are used as the oxidizing agent, it is possible to reduce the generation of harmful chemical substances that adversely affect the subsequent processing steps.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram showing an overall configuration of a water treatment system to which a water treatment reaction tank according to a first embodiment of the present invention is applied. As shown in FIG. 1, the water treatment system 1 according to the present embodiment includes a water pipe 11 through which treated water or treated water flows, a landing well 21, a mixing basin 31, a flock formation basin 41, and a sedimentation basin 51. And a rapid filtration basin 61, a water treatment reaction tank 71 according to an embodiment of the present invention, an activated carbon adsorption basin 91, and a water purification basin 101, which are installed by a landing well 21 via a water pipe 11. They are arranged in order from the upstream side. The water to be treated flows through the water pipe 11 to the landing well 21 and is treated, and then the water is treated sequentially from the mixing basin 31 to the water purification basin 101 through the water pipe 11, and finally the treated water. It is discharged from the water pipe 11 on the downstream side where the water purification tank 101 is installed. In addition, the kind of installation and the number of installation which comprise the water treatment system 1 of this invention are not limited to the example shown in FIG.

  Next, the configuration of each facility will be described (Japan Waterworks Association, “Waterworks Dictionary (Second Edition)” (Tokyo, Japan Waterworks Association, 1996)). In addition, the detail of the reaction tank 71 for water treatment concerning embodiment of this invention is mentioned later.

  The landing well 21 is a pond or a trout (basin) provided to stabilize the fluctuation of the raw water level flowing into the water purification plant or the like and to adjust the water level and measure the amount of inflow.

  The mixing basin 31 is a mixing device for giving a rapid stirring immediately after injecting the flocculant so that the flocculant is uniformly distributed in the raw water.

  The flock formation pond 41 is a pond for performing flock formation as a pretreatment for the precipitation process.

  The sedimentation basin 51 uses the principle that particles that are heavier than water settle and separate from water in still water or in a very quiet flow. A pond that separates particles.

  The rapid filtration basin 61 is a filtration tank for filtering and removing the remaining turbid matter after performing the coagulation sedimentation treatment.

  The activated carbon adsorption pond 91 utilizes the excellent adsorption ability of activated carbon, and utilizes the decomposition action of microorganisms grown on the activated carbon surface, so that organic substances such as off-flavors, chromaticity, anionic surfactants, and phenols are used. Is to be removed.

  In the water purification plant 101, the water purification basin 101 relieves the non-uniformity between the filtered water volume and the water volume that occurs in the operation management of the water purification process, and supplies purified water to cope with the fluctuation of the water volume at the time of accident or water quality abnormality. It is to be stored.

  Next, the water treatment reaction tank according to the first embodiment of the present invention will be described. Each water treatment reaction tank may contain a plurality of constituent elements to be described later, and the constituent elements other than the constituent elements. May be included, or some of the components described below may not be included. Further, the installation location of each component is not particularly limited as long as the present invention functions as intended. In addition, about the part which has the same function in each reaction tank for water treatment, the description is abbreviate | omitted only in 1st Embodiment in order to avoid duplication of description, and the description after 2nd Embodiment is abbreviate | omitted.

  FIG. 2 is a block diagram showing a water treatment reactor according to the first embodiment of the present invention. As shown in FIG. 2, the water treatment reaction tank 71 of the present invention is a so-called diffuser type or diffuser type reaction tank. Here, the diffuser type reaction tank is a system in which ozone gas is blown from the bottom (in the present invention, the bottom of the reaction tank 211) using a porous diffuser (in the present invention, the ozone gas injection pipe 221). Is. This is the most commonly used water treatment using ozone because it can handle small to large flow rates and is flexible in operation (Ozone Handbook, written by Isao Somiya) ( (Yokohama, Sanyu Shobo, 2004), Isao Munemiya, “Ozone-Used Water Treatment Technology” (Pollution Control Technology Doyukai, 1989)). In the present embodiment, a reaction tank 211 that stores treated water flowing through the water pipe 11, an ozone gas generator (not shown) that generates ozone gas, and ozone gas is injected into the reaction tank 211, and the treated water and An ozone gas injection pipe 221 to be contacted, a dissolved ozone concentration meter 231 that measures the concentration of dissolved ozone in the water to be treated, and an injection amount of hydrogen peroxide are determined based on the dissolved ozone concentration and transmitted to the hydrogen peroxide injection device 251 A feedback control device 241 for controlling the injection amount, a hydrogen peroxide injection device 251 for injecting hydrogen peroxide into the hydrogen peroxide injection pipe 261 in response to a signal from the feedback control device 241, and hydrogen peroxide for water supply It is comprised with the water pipe 11 which flows in into a pipe | tube. The water to be treated flows into the reaction tank 211 through the water pipe 11 and is stored in an appropriate amount, and then ozone gas is injected from the ozone gas injection pipe 221 to generate dissolved ozone in contact with the water to be treated. It is measured by a dissolved ozone concentration meter 231 installed on the outlet side of 211. Based on this dissolved ozone concentration, the amount of hydrogen peroxide injected is determined by the feedback control device 241, and then hydrogen peroxide flows into the reaction tank 211 from the hydrogen peroxide injector 251 through the hydrogen peroxide injection pipe 261. Then, the water is purified and discharged from the water pipe 11 installed on the outlet side of the reaction tank 211.

  Next, the method for controlling the injection amount of hydrogen peroxide according to the present invention will be described based on the principle of water treatment.

  In normal ozone treatment, as shown in FIG. 3, a reaction by dissolved ozone ((B) in the figure) and a reaction by hydroxyl radicals generated by decomposition of dissolved ozone ((D) in the figure) Oxidative decomposition of the material to be treated is performed by two routes. In this case, the rate at which the substance to be treated is decomposed by dissolved ozone ((B) in the figure) and the rate at which dissolved ozone self-decomposes ((C) in the figure, partly converted to hydroxyl radicals due to self-decomposition) )) Is very slow compared to the rate at which ozone gas dissolves in the water to be treated and generates dissolved ozone ((A) in the figure), so dissolved ozone accumulates in the reaction tank. The production speed of (A) is reduced. Therefore, in the normal ozone treatment, considering the entire mass balance, as shown in FIG. 4, not only a part of the dissolved ozone generated by dissolving the ozone gas remains in the reaction tank without being consumed. Since undissolved ozone gas (unused ozone gas in the figure) also remains, the overall processing efficiency decreases.

  Thus, hydroxyl radicals such as those disclosed in JP-A-9-276882 (Section 11, FIG. 1) and JP-A-10-165971 (Section 8, FIG. 1) are disclosed. Attempts have been made to improve treatment efficiency by introducing an accelerated oxidation treatment method in which hydrogen peroxide is added to ozone gas, which is a supply source of the above. As shown in FIG. 5, in the accelerated oxidation treatment method, ozone injected as ozone gas dissolves in the water to be treated and then reacts with the added hydrogen peroxide to generate hydroxyl radicals, and the substance to be treated is decomposed. The However, in this case, if the amount of hydrogen peroxide is not optimized and hydrogen peroxide is insufficient, the rate at which dissolved ozone is decomposed (the sum of (B) and (C) in the figure) is Since ozone gas dissolves in the water to be treated and is slower than the rate at which dissolved ozone is generated ((A) in the figure), dissolved ozone accumulates in the reaction tank as in normal ozone treatment. The production speed of (A) is reduced. Therefore, in the accelerated oxidation treatment method, considering the overall mass balance, as shown in FIG. 6, the amount of residual dissolved ozone is reduced as compared with the case of performing normal ozone treatment, but it remains together with undissolved ozone gas. As a result, the overall processing efficiency decreases.

  On the other hand, in the present invention, as shown in FIG. 7, the accelerated oxidation treatment method is applied in the same manner as described above, and hydrogen peroxide is added. In this case, since the amount of hydrogen peroxide added is optimized, the rate at which ozone gas dissolves in the water to be treated to generate dissolved ozone ((A) in the figure) and the rate at which dissolved ozone is decomposed (in the figure) (Sum of (B) and (C)) is equivalent speed, and dissolved ozone is not accumulated. Since dissolved ozone mainly reacts with hydrogen peroxide, the target substance is mainly decomposed by the generated hydroxyl radicals. Therefore, the generation rate of the above (A) can always keep the maximum rate, and considering the overall mass balance, almost no undissolved ozone gas remains as shown in FIG. Will improve.

  That is, the difference between the two lies in the overall mass balance control method. As shown in FIG. 9, the control method in the accelerated oxidation treatment of the prior art is determined by the ratio of ozone gas and hydrogen peroxide, and this ratio is a numerical value set in advance for both the prior arts. Therefore, even if the numerical value calculated at the laboratory scale is introduced in an actual facility, fine adjustment is necessary, and depending on the actual water quality of the treated water, the shape of the apparatus, etc., it is not possible to perform processing using this numerical value. There is also a possibility that it will take the labor and time of the operator, and the overall processing efficiency is expected to decrease.

  However, as shown in FIG. 10, the control method in the accelerated oxidation treatment of the present invention optimizes the injection amount of hydrogen peroxide using dissolved ozone concentration as an index. There is no need to spend effort and time fine-tuning the facility. Here, optimization of the injection amount of hydrogen peroxide is a condition that maximizes the dissolved amount of ozone gas when ozone gas of unknown concentration is injected into the reaction tank, that is, a condition for obtaining good treatment efficiency. And the injection amount of hydrogen peroxide is calculated from the conditions. The change in ozone gas concentration in the reaction tank is expressed by the following formula (I)

( _Where [O ₃ ] _gas (mg / L) is the ozone gas concentration, K _La (1 / s) is the overall ozone transfer capacity coefficient, [O ₃ ] _liq (mg / L) is the dissolved ozone concentration, [O ₃ ] ^* _liq (mg / L) represents a saturated dissolved ozone concentration.) The condition that the injected ozone gas is utilized to the maximum is also the condition that the amount of decrease in ozone gas (the amount dissolved in the water to be treated) for each elapsed time is maximized. From the formula (I), it can be seen that when the dissolved ozone concentration is low, the dissolution rate of the ozone gas into the water to be treated is high, and the dissolved ozone reacts with the hydrogen peroxide solution to generate hydroxyl radicals. The rate increases when the hydrogen peroxide concentration is high. Therefore, if an amount of hydrogen peroxide that reacts with the total dissolved ozone for each elapsed time is present in the reaction tank, the dissolution rate of the ozone gas is always maximized.

  Therefore, in the above-described normal ozone treatment, the dissolved ozone concentration at the outlet of the reaction tank becomes the highest, so that dissolved ozone is detected at the outlet of the reaction tank in order to always maximize the dissolution rate of the ozone gas described above. If not, it is considered that it is not detected from other points in the reaction tank. Therefore, as shown in FIG. 2, the dissolved ozone concentration meter 231 is desirably installed at the outlet of the reaction tank 211.

  Further, the feedback control device 241 preferably reduces the amount of dissolved ozone based on the dissolved ozone concentration detected by the dissolved ozone concentration meter 231. More preferably, the amount of dissolved ozone is minimized. It is desirable to be designed to be controllable. In addition, since it is desirable that the injection amount is small from the viewpoint of reducing the processing efficiency and increasing the economic burden when hydrogen peroxide is excessive, the feedback control device 241 always maximizes the ozone gas dissolution rate. May be set on condition that the necessary injection amount, preferably the minimum necessary injection amount. Moreover, even when it becomes necessary to set the upper limit or the lower limit of the amount of hydrogen peroxide to be added from another viewpoint, the design may be changed as appropriate according to the situation. Furthermore, when the accuracy of the dissolved ozone concentration meter 231 to be installed is low due to the difference in accuracy of the dissolved ozone concentration meter 231, the injection amount of hydrogen peroxide can be controlled based on the dissolved ozone concentration lower than the detection limit value. May be designed.

  Next, other embodiments of the water treatment reactor according to the present invention will be described. These are similar to the water treatment reactor according to the first embodiment, for example, in a water treatment system as shown in FIG. Applicable.

  FIG. 11: is a block diagram which shows the reaction tank for water treatment concerning the 2nd Embodiment of this invention. As shown in FIG. 11, the water treatment reaction tank 72 of the present invention is different from the water treatment reaction tank of the first embodiment of the present invention, and is a multistage type in which a plurality of reaction tanks 211a, 211b, 211c are connected in series. It is a reaction tank. A dissolved ozone concentration meter 231 for measuring the concentration of dissolved ozone in the water to be treated is installed at the outlet of the reaction vessel 211c, and the feedback control device 241 is dissolved in the reaction vessel 211c measured by the dissolved ozone concentration meter 231. Based on the ozone concentration, the injection amount of hydrogen peroxide can be controlled. That is, in this embodiment, since there is one injection site of hydrogen peroxide as in the first embodiment, the dissolved ozone concentration in the reaction tank 211c is measured to measure the concentration of dissolved ozone in the reaction tanks 211a to 211c. Equivalent to measuring the dissolved ozone concentration. In addition, about the other structure, the control method of the injection amount of ozone and hydrogen peroxide, and the water treatment principle, it is the same as that of the reaction tank for water treatment of the 1st Embodiment of this invention.

  FIG. 12 is a block diagram showing a water treatment reactor according to the third embodiment of the present invention. As shown in FIG. 12, the water treatment reaction tank 73 of the present invention is a multistage type in which a plurality of reaction tanks 211a, 211b, and 211c are connected in series, similarly to the water treatment reaction tank of the second embodiment of the present invention. A dissolved ozone concentration meter 231 for measuring the concentration of dissolved ozone in the water to be treated is installed at the outlet of the reaction tank 211c. However, unlike the water treatment reactor of the second embodiment of the present invention, the feedback control devices 241a to 241c are each based on the concentration of dissolved ozone in the water to be treated measured by the dissolved ozone concentration meter 231. The injection amount of hydrogen peroxide into the reaction vessels 211a to 211c is configured to be controllable. That is, compared with the second embodiment, this embodiment has hydrogen peroxide injection devices 251a to 251c in the respective reaction tanks 211a to 211c. Therefore, in the previous reaction tank 211a, the subsequent reaction tanks 211b, It is not necessary to inject excessive hydrogen peroxide necessary for 211c, and it is sufficient to inject a minimum amount of hydrogen peroxide in each of the reaction tanks 211a to 211c. At this time, the injection amount of hydrogen peroxide can be controlled for each of the hydrogen peroxide injection devices 251a to 251c, or the injection amount can be controlled only for a specific hydrogen peroxide injection device. In addition, about the other structure, the control method of the injection amount of ozone and hydrogen peroxide, and the water treatment principle, it is the same as that of the reaction tank for water treatment of the 1st Embodiment of this invention.

  FIG. 13: is a block diagram which shows the reaction tank for water treatment concerning the 4th Embodiment of this invention. As shown in FIG. 13, the water treatment reaction tank 74 of the present invention is a multistage type in which a plurality of reaction tanks 211a, 211b, and 211c are connected in series, similarly to the water treatment reaction tank of the second embodiment of the present invention. It is a reaction tank. However, unlike the water treatment reaction tank of the second embodiment of the present invention, the dissolved ozone concentration meters 231a, 231b, and 231c for measuring the concentration of dissolved ozone in the water to be treated are reaction tanks 211a, 211b, and 211c. The concentration of dissolved ozone in the treated water measured by the dissolved ozone concentration meter 231a, the concentration of dissolved ozone in the treated water measured by the dissolved ozone concentration meter 231b, and the dissolved ozone concentration The feedback control device 241a, the feedback control device 241b, and the feedback control device 241c can control the injection amount of hydrogen peroxide into the reaction tank 211a based on the concentration of dissolved ozone in the treated water measured by the total 231c. It is configured. At this time, the hydrogen peroxide injection device 251 may be configured to be able to inject the hydrogen peroxide injection amounts calculated by the two control devices into the hydrogen peroxide injection pipe 261 separately or at a time. That is, as in this embodiment, when a plurality of reaction vessels 211a to 211c are connected in series, the ozone gas injection rate may be changed in each reaction vessel 211a to 211c. At this time, the dissolved ozone concentration at the outlet of the reaction tank where the injection rate of ozone gas is high may be higher than the dissolved ozone concentration at the final outlet (in this embodiment, the outlet of the reaction tank 211c). In this embodiment, since the dissolved ozone concentration meters 231a to 231c are installed at the outlets of the reaction vessels 211a to 211c, even when the processing conditions such as the ozone gas injection rate are different in the reaction vessels 211a to 211c, In each reaction tank 211a-211c, it can process on optimal process conditions. In addition, about the other structure, the control method of the injection amount of ozone and hydrogen peroxide, and the water treatment principle, it is the same as that of the reaction tank for water treatment of the 1st Embodiment of this invention.

  FIG. 14: is a block diagram which shows the reaction tank for water treatment concerning the 5th Embodiment of this invention. As shown in FIG. 14, the water treatment reaction tank 75 of the present invention is a multistage type in which a plurality of reaction tanks 211a, 211b, and 211c are connected in series, similarly to the water treatment reaction tank of the second embodiment of the present invention. It is a reaction tank. However, unlike the water treatment reaction tank of the second embodiment of the present invention, the dissolved ozone concentration meters 231a, 231b, and 231c for measuring the concentration of dissolved ozone in the water to be treated are reaction tanks 211a, 211b, and 211c. The feedback control devices 241a, 241b, and 241c are respectively installed at the outlets of the reaction tanks 211a, 211b based on the concentrations of dissolved ozone in the water to be treated measured by the dissolved ozone concentration meters 231a, 231b, 231c. , 211c, the amount of hydrogen peroxide injected is controlled. That is, since this embodiment has a configuration in which the third embodiment and the fourth embodiment are combined, reaction conditions such as an ozone gas injection rate in each of the reaction tanks 211a to 211c of the multistage reaction tank. Even if they are different from each other, the minimum hydrogen peroxide can be injected into each of the reaction vessels 211a to 211c. In addition, about the other structure, the control method of the injection amount of ozone and hydrogen peroxide, and the water treatment principle, it is the same as that of the reaction tank for water treatment of the 1st Embodiment of this invention.

  FIG. 15: is a block diagram which shows the reaction tank for water treatment concerning the 6th Embodiment of this invention. As shown in FIG. 15, the water treatment reaction tank 76 of the present invention is a multistage type in which a plurality of reaction tanks 211a, 211b, and 211c are connected in series, similarly to the water treatment reaction tank of the second embodiment of the present invention. A dissolved ozone concentration meter 231 for measuring the concentration of dissolved ozone in the water to be treated is installed at the outlet of the reaction tank 211c. However, unlike the water treatment reactor of the second embodiment of the present invention, the hydrogen peroxide injector 251 is installed at the inlet of the reactor 211b, and the feedback controller 241 is measured by the dissolved ozone concentration meter 231. The injection amount of hydrogen peroxide can be controlled based on the dissolved ozone concentration in the reaction tank 211c. That is, a component having high reactivity with ozone exists to some extent in the water to be treated. In the present embodiment, components that are highly reactive with ozone are preferentially decomposed in the first reaction tank 211a by ozone treatment, and the remaining hardly ozone-reactive components are ozone / peroxidized in the subsequent reaction tanks 211b and 211c. It will be decomposed by hydrogen treatment. Therefore, in the case of the configuration of this embodiment, it is not necessary to inject unnecessary hydrogen peroxide in the first reaction tank 211a. It is also possible to control the dissolved ozone concentration by installing a dissolved ozone concentration meter at the outlet of the first-stage reaction tank 211a. The configuration of the subsequent ozone / hydrogen peroxide treatment is the same as in the second embodiment, and the dissolved ozone concentration in the reaction vessels 211b and 211c is controlled by the dissolved ozone concentration at the outlet of the reaction vessel 211c. Become. In addition, about the other structure, the control method of the injection amount of ozone and hydrogen peroxide, and the water treatment principle, it is the same as that of the reaction tank for water treatment of the 1st Embodiment of this invention.

  FIG. 16: is a block diagram which shows the reaction tank for water treatment concerning the 7th Embodiment of this invention. As shown in FIG. 16, the water treatment reaction tank 77 of the present invention is a multistage type in which a plurality of reaction tanks 211a, 211b, and 211c are connected in series, similarly to the water treatment reaction tank of the second embodiment of the present invention. A dissolved ozone concentration meter 231 for measuring the concentration of dissolved ozone in the water to be treated is installed at the outlet of the reaction tank 211c. However, unlike the water treatment reactor of the second embodiment of the present invention, the feedback control devices 241a and 241b are respectively based on the concentration of dissolved ozone in the water to be treated measured by the dissolved ozone concentration meter 231. The amount of hydrogen peroxide injected into the reaction vessels 211b and 211c can be controlled. That is, this embodiment has a configuration in which the third embodiment and the sixth embodiment are combined. For this reason, in the first reaction tank 211a, components having high reactivity with ozone are preferentially decomposed by ozone treatment, and in the subsequent reaction tanks 211b and 211c, remaining ozone-reactive components are treated with ozone / hydrogen peroxide. It will be decomposed by. In the case of the configuration of this embodiment, it is not necessary to inject unnecessary hydrogen peroxide in the first reaction tank 211a. As in the case of the sixth embodiment, a dissolved ozone concentration meter can be installed at the outlet of the first-stage reaction tank 211a to control the dissolved ozone concentration. In the subsequent ozone / hydrogen peroxide treatment, as in the third embodiment, it is not necessary to excessively inject the hydrogen peroxide required in the subsequent reaction tank 211c in the previous reaction tank 211b. At this time, the injection amount of hydrogen peroxide can be controlled for each of the hydrogen peroxide injection devices 251a and 251b, or the injection amount can be controlled only for a specific hydrogen peroxide injection device. In addition, about the other structure, the control method of the injection amount of ozone and hydrogen peroxide, and the water treatment principle, it is the same as that of the reaction tank for water treatment of the 1st Embodiment of this invention.

  FIG. 17: is a block diagram which shows the reaction tank for water treatment concerning the 8th Embodiment of this invention. As shown in FIG. 17, the water treatment reaction tank 78 of the present invention is a multistage type in which a plurality of reaction tanks 211a, 211b, and 211c are connected in series, similarly to the water treatment reaction tank of the second embodiment of the present invention. It is a reaction tank. However, unlike the water treatment reaction tank of the second embodiment of the present invention, the dissolved ozone concentration meters 231a and 231b for measuring the concentration of dissolved ozone in the water to be treated are provided at the outlets of the reaction tanks 211b and 211c. A feedback control device is installed based on the concentration of dissolved ozone in the treated water measured by the dissolved ozone concentration meter 231a and the concentration of dissolved ozone in the treated water measured by the dissolved ozone concentration meter 231b. The 241a and the feedback control device 241b are configured to be able to control the injection amount of hydrogen peroxide into the reaction tank 211b. At this time, the hydrogen peroxide injection device 251 may be configured to be able to inject the hydrogen peroxide injection amounts calculated by the two control devices into the hydrogen peroxide injection pipe 261 separately or at a time. That is, this embodiment has a configuration in which the fourth embodiment and the sixth embodiment are combined. For this reason, in the first reaction tank 211a, components having high reactivity with ozone are preferentially decomposed by ozone treatment, and in the subsequent reaction tanks 211b and 211c, remaining ozone-reactive components are treated with ozone / hydrogen peroxide. It will be decomposed by. In the case of the configuration of this embodiment, it is not necessary to inject unnecessary hydrogen peroxide in the first reaction tank 211a. As in the case of the sixth embodiment, a dissolved ozone concentration meter can be installed at the outlet of the first-stage reaction tank 211a to control the dissolved ozone concentration. In the subsequent ozone / hydrogen peroxide treatment, when the treatment conditions such as the ozone gas injection rate are changed in the respective reaction vessels 211b and 211c, the dissolved ozone concentration at the exit of a certain reaction vessel is the final exit (in this embodiment, The concentration of dissolved ozone at the outlet of the reaction tank 211c may be higher. In the configuration of the sixth embodiment, similarly to the fourth embodiment, the dissolved ozone concentration meters 231a and 231b are installed at the outlets of the respective ozone reaction tanks 211b and 211c. Even when the processing conditions are different between the tanks 211b and 211c, the treatment can be performed under the optimal processing conditions in the respective ozone reaction tanks 211b and 211c. In addition, about the other structure, the control method of the injection amount of ozone and hydrogen peroxide, and the water treatment principle, it is the same as that of the reaction tank for water treatment of the 1st Embodiment of this invention.

  FIG. 18: is a block diagram which shows the reaction tank for water treatment concerning the 9th Embodiment of this invention. As shown in FIG. 18, the water treatment reaction tank 79 of the present invention is a multistage type in which a plurality of reaction tanks 211a, 211b, and 211c are connected in series, similarly to the water treatment reaction tank of the second embodiment of the present invention. It is a reaction tank. However, unlike the water treatment reaction tank of the second embodiment of the present invention, the dissolved ozone concentration meters 231a and 231b for measuring the concentration of dissolved ozone in the water to be treated are provided at the outlets of the reaction tanks 211b and 211c. The feedback control devices 241a and 241b are respectively installed, and the hydrogen peroxide is injected into the reaction tanks 211b and 211c based on the concentration of dissolved ozone in the water to be treated measured by the dissolved ozone concentration meters 231a and 231b, respectively. Each amount is configured to be controllable. That is, this embodiment has a configuration in which the fifth embodiment and the sixth embodiment are combined. For this reason, in the first reaction tank 211a, components having high reactivity with ozone are preferentially decomposed by ozone treatment, and in the subsequent reaction tanks 211b and 211c, remaining ozone-reactive components are treated with ozone / hydrogen peroxide. It will be decomposed by. In the case of the configuration of this embodiment, it is not necessary to inject unnecessary hydrogen peroxide in the first reaction tank 211a. As in the case of the sixth embodiment, a dissolved ozone concentration meter can be installed at the outlet of the first-stage ozone reaction tank 211a to control the dissolved ozone concentration. In the subsequent ozone / hydrogen peroxide treatment, as in the fifth embodiment, even if the reaction conditions such as the ozone gas injection rate differ between the reaction tanks 211b and 211c, the minimum necessary for each reaction tank 211b and 211c. A limited amount of hydrogen peroxide can be injected. In addition, about the other structure, the control method of the injection amount of ozone and hydrogen peroxide, and the water treatment principle, it is the same as that of the reaction tank for water treatment of the 1st Embodiment of this invention.

  FIG. 19: is a block diagram which shows the reaction tank for water treatment concerning the 10th Embodiment of this invention. As shown in FIG. 19, the water treatment reaction tank 80 of the present invention is called an ejector reaction tank or an ink jet reaction tank, unlike the water treatment reaction tank of the second embodiment of the present invention. The ejector-type reaction tank feeds water to be treated to which hydrogen peroxide has been added to a nozzle (not shown), sucks ozone gas through the ozone gas injection pipe 221 using the pressure difference at the nozzle, and supplies the water pipe 11 It is the reaction tank of the type disperse | distributed in the reaction tank 211 through. That is, in the embodiment of the present invention, the means for injecting ozone gas and hydrogen peroxide into the reaction tank 211 is different from the water treatment reaction tank according to the first to ninth embodiments of the present invention. The ejector 271 is a compact device, the dispersed bubbles are fine, the gas-liquid mixture is intense, a large mass transfer coefficient is obtained, and the diffuser (reaction for water treatment according to the first to ninth embodiments of the present invention). High ozone dissolution efficiency can be obtained in a short time without the need for deep water depth as in the method used in the tank. Therefore, it is an effective method for a small scale, and is applied to advanced water and sewage treatment. Further, in the water treatment reaction tank 80 which is an ejector type reaction tank, the ozone gas is dissolved in the ejector 271, but the residual ozone gas is also absorbed in the reaction tank 211. Therefore, in this embodiment, the dissolved ozone concentration in the ejector 271 and the reaction vessel 211 is measured and controlled by measuring the dissolved ozone concentration in the reaction vessel 211. In addition, about the other structure, the control method of the injection amount of ozone and hydrogen peroxide, and the water treatment principle, it is the same as that of the reaction tank for water treatment of the 1st Embodiment of this invention.

  FIG. 20 is a block diagram showing a water treatment reactor according to the eleventh embodiment of the present invention. As shown in FIG. 20, the water treatment reaction tank 81 of the present invention is called an ejector-type reaction tank or an ink jet reaction tank, similarly to the water treatment reaction tank according to the tenth embodiment of the present invention. . However, unlike the water treatment reaction tank according to the tenth embodiment of the present invention, a dissolved ozone concentration meter 231 is disposed between the ejector 271 and the reaction tank 211. Further, in the case of the water treatment reaction tank 81 which is an ejector-type reaction tank, depending on the performance of the ejector 271 and the ozone injection amount, all of the injected ozone gas may be dissolved by the ejector 271. In this case, the dissolved ozone concentration is considered to be highest at the exit of the ejector 271. In this embodiment, the dissolved ozone concentration is measured and controlled specifically for the ejector 271. In addition, about the other structure, the control method of the injection amount of ozone and hydrogen peroxide, and the water treatment principle, it is the same as that of the reaction tank for water treatment of the 1st Embodiment of this invention.

  FIG. 21 is a block diagram showing a water treatment reactor according to a twelfth embodiment of the present invention. As shown in FIG. 21, the water treatment reaction tank 82 according to the present invention is called an ejector reaction tank or an ink jet reaction tank, similarly to the water treatment reaction tank according to the tenth embodiment of the present invention. A dissolved ozone concentration meter 231 for measuring the concentration of dissolved ozone in the water to be treated is installed at the outlet of the reaction tank 211. However, unlike the water treatment reactor according to the tenth embodiment of the present invention, the feedback control devices 241a and 241b are based on the concentration of dissolved ozone in the treated water measured by the dissolved ozone concentration meter 231. The amounts of hydrogen peroxide injected into the ejector 271 and the reaction tank 211 are respectively controlled. That is, in the present embodiment, compared to the tenth embodiment, the hydrogen peroxide injection devices 251a and 251b are disposed in the ejector 271 and the reaction tank 211, respectively, so that hydrogen peroxide can be injected. It becomes possible to inject a minimum amount of hydrogen peroxide into each of the ejector 271 and the reaction tank 211, and it is not necessary to inject excess hydrogen peroxide in the reaction in the ejector 271. At this time, the injection amount of hydrogen peroxide can be controlled for each of the hydrogen peroxide injection devices 251a and 251b, or the injection amount can be controlled only for a specific hydrogen peroxide injection device.

  FIG. 22 is a block diagram showing a water treatment reactor according to a thirteenth embodiment of the present invention. As shown in FIG. 22, the water treatment reaction tank 83 of the present invention is called an ejector-type reaction tank or an ink jet reaction tank, similarly to the water treatment reaction tank according to the tenth embodiment of the present invention. . However, unlike the water treatment reaction tank according to the tenth embodiment of the present invention, dissolved ozone concentration meters 231a and 231b are disposed between the ejector 271 and the reaction tank 211 and at the outlet of the reaction tank 211, respectively. Based on the concentration of each dissolved ozone in the treated water measured by the dissolved ozone concentration meter 231a and the concentration of each dissolved ozone in the treated water measured by the dissolved ozone concentration meter 231b, The feedback control device 241b is configured to be able to control the amount of hydrogen peroxide injected into the reaction vessel 211. At this time, the hydrogen peroxide injection device 251 may be configured to be able to inject the hydrogen peroxide injection amounts calculated by the two control devices into the hydrogen peroxide injection pipe 261 separately or at a time. In the present embodiment, dissolved ozone concentration meters 231a and 231b are installed in the ejector 271 and the ozone reaction tank 211, respectively, and the tenth embodiment and the eleventh embodiment are combined. . As described above, depending on the performance and processing conditions of the ejector 271, ozone gas may be dissolved in water only by the ejector 271, or may be dissolved in water by both the ejector 271 and the reaction tank 211. In the configuration of the present embodiment, the dissolved ozone concentration is measured and controlled so as to be able to cope with either case. In addition, about the other structure, the control method of the injection amount of ozone and hydrogen peroxide, and the water treatment principle, it is the same as that of the reaction tank for water treatment of the 1st Embodiment of this invention.

  FIG. 23 is a block diagram showing a water treatment reactor according to a fourteenth embodiment of the present invention. As shown in FIG. 23, the water treatment reaction tank 84 of the present invention is called an ejector-type reaction tank or an ink jet reaction tank, similarly to the water treatment reaction tank according to the tenth embodiment of the present invention. . However, unlike the water treatment reaction tank according to the tenth embodiment of the present invention, the dissolved ozone concentration meters 231a and 231b for measuring the concentration of dissolved ozone in the water to be treated include an ejector 271 and a reaction tank 211. The feedback control devices 241a and 241b are respectively installed at the outlet of the reaction tank 211 and based on the concentration of dissolved ozone in the water to be treated measured by the dissolved ozone concentration meters 231a and 231b. 271 and the amount of hydrogen peroxide injected into the reaction tank 211 are controlled. In FIG. 23, dissolved ozone concentration meters 231a and 231b and hydrogen peroxide injectors 251a and 251b are installed in the ejector 271 and the reaction tank 211, respectively. For this reason, similarly to the case of the thirteenth embodiment, the dissolved ozone concentration at the point where the dissolved ozone concentration becomes high can be measured and controlled regardless of the performance and processing conditions of the ejector 271. Further, as in the case of the twelfth embodiment, it becomes possible to inject a minimum amount of hydrogen peroxide into each of the ejector 271 and the reaction tank 211, and excess hydrogen peroxide in the reaction in the ejector 271. There is no need to inject. In addition, about the other structure, the control method of the injection amount of ozone and hydrogen peroxide, and the water treatment principle, it is the same as that of the reaction tank for water treatment of the 1st Embodiment of this invention.

  FIG. 24 is a block diagram showing a water treatment reaction tank according to the fifteenth embodiment of the present invention. As shown in FIG. 24, the water treatment reaction tank 85 of the present invention is called a U tube type reaction tank or a downward injection type reaction tank, and generally has a deeper water depth than a diffuser type reaction tank. It is said that the absorption rate of ozone gas is high because the ozone partial pressure becomes high (Ozone Handbook, edited by Isao Somiya (Yokohama, Sanyu Shobo, 2004)). In the present embodiment, the reaction tank 212 is constituted by a double pipe in which an inner pipe 281 is arranged in a vertical cylindrical closed pipe having a water depth of 20 m to 35 m, and the inner pipe 281 is connected to the water pipe 11, The treated water flows through the inner pipe 281. The ozone gas injection pipe 221 is installed in the inner pipe 281, and the ozone gas is drawn into the water to be treated there. The water to be treated and the ozone gas descending to the bottom of the inner pipe 281 are guided to the outer annular band, converted into an upward flow, rise, and overflow into an outflow tank 291 provided at the upper part of the downward pipe. Here, the residual ozone gas is discharged from an exhaust ozone pipe (not shown), and the treated water flows out from the water pipe 11. The feedback controller 241 controls the injection amount of hydrogen peroxide into the reaction tank 212 based on the dissolved ozone concentration obtained by measuring the dissolved ozone concentration of the treated water in the outflow tank 291 by the dissolved ozone concentration meter 231. Further, in the water treatment reaction tank 85 which is a U tube type reaction tank, ozone gas is dissolved in water with different ozone absorption characteristics in each of the inner tube 281 and the reaction tank 212. By installing one dissolved ozone concentration meter 231 at the outlet of the tank 212, the dissolved ozone concentration in the inner tube 281 and the reaction tank 212 is controlled. In addition, about the other structure, the control method of the injection amount of ozone and hydrogen peroxide, and the water treatment principle, it is the same as that of the reaction tank for water treatment of the 1st Embodiment of this invention.

  FIG. 25 is a block diagram showing a water treatment reaction tank according to the sixteenth embodiment of the present invention. As shown in FIG. 25, the water treatment reaction tank 86 of the present invention is called a U-tube reaction tank or a downward injection reaction tank. The water treatment reaction tank 86, which is a U-tube reaction tank, has a higher ozone gas penetration rate as the water depth increases as it passes through the inner pipe 281. Therefore, depending on the ozone gas injection rate, the outlet of the inner pipe 281 is increased. In ozone, all ozone gas may be dissolved in water. In the present embodiment, a dissolved ozone concentration meter 231 is installed at the outlet of the inner tube 281. In order to cope with such processing conditions, the dissolved ozone concentration is measured and controlled exclusively for the inner tube 281. Become. In addition, about the other structure, the control method of the injection amount of ozone and hydrogen peroxide, and the water treatment principle, it is the same as that of the reaction tank for water treatment of the 1st Embodiment of this invention.

  FIG. 26 is a block diagram showing a water treatment reaction tank according to the seventeenth embodiment of the present invention. As shown in FIG. 26, the water treatment reaction tank 87 of the present invention is called a U-tube reaction tank or a downward injection reaction tank. In this embodiment, hydrogen peroxide injection devices 251a and 251b are installed in the inner tube 281 and the reaction vessel 212 of the water treatment reaction vessel 87, which is a U tube type reaction vessel. For this reason, it is possible to inject a minimum amount of hydrogen peroxide into each of the inner tube 281 and the reaction tank 212, and it is not necessary to inject excess hydrogen peroxide in the reaction in the inner tube 281. In addition, about the other structure, the control method of the injection amount of ozone and hydrogen peroxide, and the water treatment principle, it is the same as that of the reaction tank for water treatment of the 1st Embodiment of this invention.

  FIG. 27 is a block diagram showing a water treatment reaction tank according to the eighteenth embodiment of the present invention. As shown in FIG. 27, the water treatment reaction tank 88 of the present invention is called a U-tube reaction tank or a downward injection reaction tank. In this embodiment, dissolved ozone concentration meters 231a and 231b are installed at the outlets of the inner tube 281 and the reaction vessel 212 of the U-tube reaction vessel, and the fifteenth embodiment and the sixteenth embodiment are combined. It becomes the composition. As described above, depending on the processing conditions, ozone gas may be dissolved in water only by the inner pipe 281 or may be dissolved in water by both the inner pipe 281 and the reaction tank 212. In the configuration of the present embodiment, the dissolved ozone concentration is measured and controlled so as to be able to cope with either case. In addition, about the other structure, the control method of the injection amount of ozone and hydrogen peroxide, and the water treatment principle, it is the same as that of the reaction tank for water treatment of the 1st Embodiment of this invention.

  FIG. 28 is a block diagram showing a water treatment reaction tank according to the nineteenth embodiment of the present invention. As shown in FIG. 28, the water treatment reaction tank 89 of the present invention is called a U-tube reaction tank or a downward injection reaction tank. In this embodiment, dissolved ozone concentration meters 231a and 231b and hydrogen peroxide injectors 251a and 251b are installed in the inner tube 281 and the reaction vessel 212 of the water treatment reactor 89, which is a U-tube reaction vessel. . For this reason, similarly to the eighteenth embodiment, the dissolved ozone concentration at the point where the dissolved ozone concentration becomes high can be measured and controlled regardless of the processing conditions. Similarly to the seventeenth embodiment, it is possible to inject a minimum amount of hydrogen peroxide into each of the inner tube 281 and the reaction tank 212, and excess hydrogen peroxide in the reaction in the inner tube 281. There is no need to inject. In addition, about the other structure, the control method of the injection amount of ozone and hydrogen peroxide, and the water treatment principle, it is the same as that of the reaction tank for water treatment of the 1st Embodiment of this invention.

  In the present invention, the ozone gas contact method is not particularly limited, and for example, a turbine type (mechanical stirring type), a microbubble generation system, or the like can be used, and either one is appropriately selected according to the purpose. do it. Further, the control method of the injection amount of ozone gas is not particularly limited, and for example, a control method based on the total organic carbon amount of the water to be treated and the ratio to the ultraviolet absorbance, which is a known control method, may be applied.

  In addition, this invention is not limited to the said embodiment, Of course, a various change can be added in the range which does not deviate from the summary of this invention.

  Next, the water treatment reactor and the water treatment method of the present invention will be described in more detail with reference to examples.

  A water treatment reaction tank (reaction tank capacity: 39 L, φ100 mm × 5000 mm) having a configuration substantially similar to that of the water treatment reaction tank 71 shown in FIG. 2 is used, and malonate ions are 2.0 to 2.3 mg / kg as a treatment target substance. Groundwater (18 ° C., pH 7.7) to which L was added was circulated as water to be treated at a water volume of 3 L / min, and treatment was performed while injecting ozone gas at 17 mg / L (flow rate: 3 L / min). Hydrogen peroxide was added at addition amounts of 0, 13, 32 and 64 mg / L, and the dissolved ozone concentration and malonate ion decomposition rate in the treated water at each addition amount were measured. In addition, the dissolved ozone concentration was measured with the dissolved ozone concentration meter (reliable measurement range 0.005-0.2 mg / L) installed in the exit side of the reaction tank. Moreover, the malonate ion decomposition rate was calculated | required by measuring the malonate ion density | concentration of the entrance side and exit side of a reaction tank using an ion chromatograph. These results are shown in FIGS. 29 and 30, respectively.

  As is clear from FIGS. 29 and 30, the malonate ion decomposition rate becomes the maximum value (58%) at the minimum hydrogen peroxide addition amount of 32 mg / L at which the dissolved ozone concentration becomes the minimum value (0 mg / L). I understood. Thus, it was confirmed that the purification treatment efficiency of the water treatment reaction tank was maximized by controlling the injection amount of hydrogen peroxide so that the dissolved ozone concentration in the treated water was minimized.

  The water treatment reaction tank, water treatment system and water treatment method of the present invention have good treatment efficiency regardless of external factors such as the quality of the water to be treated and its fluctuation, the injection rate of ozone gas, the shape of the reactor, etc. Since it can be obtained, it can be applied to various water treatments such as water and sewage and industrial wastewater from factories.

It is a block diagram showing the whole water treatment system composition to which the reaction tank for water treatment concerning a 1st embodiment of the present invention was applied. It is a block diagram which shows the reaction tank for water treatment concerning the 1st Embodiment of this invention. It is the conceptual diagram which showed the outline of the normal ozone process typically. It is the conceptual diagram shown typically which showed the final mass balance of normal ozone treatment. It is the conceptual diagram which showed the outline of the accelerated oxidation process of a prior art typically. It is the conceptual diagram shown typically which showed the final mass balance of the accelerated oxidation process of a prior art. It is the conceptual diagram which showed the outline of the accelerated oxidation process of this invention typically. It is the conceptual diagram shown typically which showed the final mass balance of the accelerated oxidation process of this invention. It is the conceptual diagram which showed typically the control method of the mass balance in the accelerated oxidation process of a prior art. It is the conceptual diagram which showed typically the control method of the mass balance in the accelerated oxidation process of this invention. It is a block diagram which shows the reaction tank for water treatment concerning the 2nd Embodiment of this invention. It is a block diagram which shows the reaction tank for water treatment concerning the 3rd Embodiment of this invention. It is a block diagram which shows the reaction tank for water treatment concerning the 4th Embodiment of this invention. It is a block diagram which shows the reaction tank for water treatment concerning the 5th Embodiment of this invention. It is a block diagram which shows the reaction tank for water treatment concerning the 6th Embodiment of this invention. It is a block diagram which shows the reaction tank for water treatment concerning the 7th Embodiment of this invention. It is a block diagram which shows the reaction tank for water treatment concerning the 8th Embodiment of this invention. It is a block diagram which shows the reaction tank for water treatment concerning the 9th Embodiment of this invention. It is a block diagram which shows the reaction tank for water treatment concerning the 10th Embodiment of this invention. It is a block diagram which shows the reaction tank for water treatment concerning the 11th Embodiment of this invention. It is a block diagram which shows the reaction tank for water treatment concerning the 12th Embodiment of this invention. It is a block diagram which shows the reaction tank for water treatment concerning the 13th Embodiment of this invention. It is a block diagram which shows the reaction tank for water treatment concerning the 14th Embodiment of this invention. It is a block diagram which shows the reaction tank for water treatment concerning the 15th Embodiment of this invention. It is a block diagram which shows the reaction tank for water treatment concerning the 16th Embodiment of this invention. It is a block diagram which shows the reaction tank for water treatment concerning the 17th Embodiment of this invention. It is a block diagram which shows the reaction tank for water treatment concerning the 18th Embodiment of this invention. It is a block diagram which shows the reaction tank for water treatment concerning the 19th Embodiment of this invention. It is a graph which shows the result (relationship of hydrogen peroxide addition amount and dissolved ozone density | concentration) obtained by the Example. It is a graph which shows the result (relationship of hydrogen peroxide addition amount and malonate ion decomposition rate) obtained by the Example.

DESCRIPTION OF SYMBOLS 1 Water treatment system 11 Water pipe 21 Irrigation well 31 Mixing basin 41 Flock formation pond 51 Sedimentation basin 61 Rapid filtration basin 71-89 Water treatment reactor 91 Activated carbon adsorption basin 101 Water purification tank 211,212 Reaction tank 221 Ozone gas injection pipe 231 Dissolved Ozone concentration meter 241 Feedback control device 251 Hydrogen peroxide injection device 261 Hydrogen peroxide injection tube 271 Ejector 281 Inner tube 291 Outflow tank

Claims (6)

Ozone gas injection means for injecting ozone gas into the water to be treated;
Hydrogen peroxide injection means for injecting hydrogen peroxide into the water to be treated;
Dissolved ozone concentration measuring means for measuring the concentration of dissolved ozone in the treated water;
A water treatment reactor to have a,
Said hydrogen peroxide injection means, characterized in that the dissolved ozone concentration measured by the dissolved ozone concentration measuring means for controlling the injection amount of the hydrogen peroxide to be less than the lower limit of the confidence measurement range, the Water treatment reactor. The water treatment reactor according to claim 1, wherein the hydrogen peroxide injection unit controls the injection amount of the hydrogen peroxide to be a minimum . It comprises at least one water treatment reaction tank, and the water treatment reaction tank comprises:
Ozone gas injection means for injecting ozone gas into the water to be treated;
Hydrogen peroxide injection means for injecting hydrogen peroxide into the water to be treated;
Dissolved ozone concentration measuring means for measuring the concentration of dissolved ozone in the treated water;
A water treatment system to have a,
Said hydrogen peroxide injection means, characterized in that the dissolved ozone concentration measured by the dissolved ozone concentration measuring means for controlling the injection amount of the hydrogen peroxide to be less than the lower limit of the confidence measurement range, the Water treatment system. The water treatment system according to claim 3 , wherein the hydrogen peroxide injection unit controls the injection amount of the hydrogen peroxide to be a minimum . An ozone gas injection step of injecting ozone gas into the water to be treated;
Hydrogen peroxide injection step of injecting hydrogen peroxide into the treated water;
A dissolved ozone concentration measuring step for measuring the concentration of dissolved ozone in the treated water;
A water treatment method to have a,
The hydrogen peroxide injection step controls the injection amount of the hydrogen peroxide so that the concentration of the dissolved ozone measured by the dissolved ozone concentration measurement step is less than a lower limit value of a reliability measurement range. the water treatment method. 6. The water treatment method according to claim 5 , wherein the hydrogen peroxide injection step is controlled so that the injection amount of the hydrogen peroxide is minimized .

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